A toothbrush is used to clean the teeth by removing plaque and debris from the tooth surfaces. Conventional toothbrushes provided with a flat bristle trim are limited in their ability to conform to the curvature of the teeth, to penetrate into the interproximal areas between the teeth, to sweep away the plaque and debris, and to clean along the gum line. Additionally, such toothbrushes have a limited ability to retain dentifrice for cleaning the teeth. During the brushing process, the dentifrice typically slips through the tufts of bristles and away from the contact between the bristles and the teeth. As a result, the dentifrice is often spread around the mouth, rather than being concentrated on the contact of the bristles with the teeth. Therefore, the efficiency of the cleaning process is reduced.
While substantial efforts have been made to modify the cleaning elements of toothbrushes to improve the efficiency of the oral cleaning process and to hold the dentifrice in place during brushing, the industry continues to pursue arrangements of cleaning elements that will improve upon the preceding technology.
In an early attempt at improving the cleaning elements, toothbrushes were developed having two or three circular brush sections which are arranged within holders that may be screwed into mating receptacles in the tooth brush handle so that they can be removed and replaced as needed. Each brush section contains stiff cleaning elements and is spaced from the other along the longitudinal axis of the handle at a distance less than the thickness of a tooth so that the brush operates on both the lingual (inside) and facial (outside) surfaces of the teeth.
Another existing toothbrush includes a head containing a flexible, rubber-like prophylaxis polishing cup or “prophy cup” similar to that used by dental personnel to professionally clean teeth. This prophy cup is loaded with toothpaste by the user and applied to the teeth. The “soft rubber-like prophy cup device follows the contours of teeth more effectively than bristles.” A ring of cleaning elements (“bristle tufts”) are placed about the periphery of the toothbrush head which co-act with the prophy cups to clean the user's teeth and gums.
More recently, the strategic arrangement and combination of cleaning elements in the form of elastomeric prophy cups and bristle tufts has become more common as a way of improving cleaning efficiency and maintaining the dentifrice in place during brushing. One example of the combined use and strategic arrangement of elastomeric prophy cups and bristle tufts is a toothbrush having a head portion comprising a plurality of inner loops formed by elastomeric walls. The central inner loop is surrounded by outer loops formed of bristles. A central cleaning element, formed as a bristle tuft, is located within the elastomeric inner loop.
Another example of the combined use and strategic arrangement of elastomeric prophy cups and bristle tufts can be found in a toothbrush having a head portion comprising a plurality of soft elastomer prophy cups surrounded by bristle rings. In another embodiment, a toothbrush exists wherein the centralized prophy cups are formed by groups of densely packed cleaning elements that are surrounded by bristle rings. The bristle rings in this toothbrush are also disclosed as having one or more tufts at an inclination.